21084353718 has 8 divisors (see below), whose sum is σ = 42168707448. Its totient is φ = 7028117904.

The previous prime is 21084353663. The next prime is 21084353747. The reversal of 21084353718 is 81735348012.

It is a sphenic number, since it is the product of 3 distinct primes.

21084353718 is an admirable number.

It is a super-4 number, since 4×21084353718⁴ (a number of 42 digits) contains 4444 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21084353718.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1757029471 + ... + 1757029482.

It is an arithmetic number, because the mean of its divisors is an integer number (5271088431).

Almost surely, 2^21084353718 is an apocalyptic number.

21084353718 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21084353718 is a wasteful number, since it uses less digits than its factorization.

21084353718 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3514058958.

The product of its (nonzero) digits is 161280, while the sum is 42.

The spelling of 21084353718 in words is "twenty-one billion, eighty-four million, three hundred fifty-three thousand, seven hundred eighteen".